Database Development: UNIT 7 IT 402 CBSE-10
Database Development
Database – A database is an organized collection of data.
For
example:- In a stationary shop, detailed records of the materials
available in the shop is database. Similarly in a computerized system,
we need to maintain several files, we would used database programs
such as Microsoft Access, OpenOffice.org Base, and MySQL. These
database programs are used to organize the data as per our needs in
the computer system.
Database Management System (DBMS) – A database management
system is a software package with computer programs that controls
the creation, maintenance and use of a database.
A DBMS allows
different user application programs to concurrently access the same
database. Some of the DBMSs are Oracle, IBM DB2, Microsoft SQL
server, Microsoft Access, PostgreSQL, MySQL, FoxPro and SQLite.
Data can be organized into two types:-
Flat File: Data is stored in a single table. Usually suitable for less
amount of data.
Relational: Data is stored in multiple tables and the tables are linked
using a common field. Relational is suitable for medium to large
amount of data.
Database Servers – Database servers are dedicated computers that
hold the actual databases and run only the DBMS and related
software. Databases on the database servers are accessed through
command line or graphic user interface tools referred to as Frontends;
database servers are referred to as Back-ends. Such type of data
access is referred to as Client-server model.
RDBMS:- A relational database management system (RDBMS) is a
database management system that is based on the relational model. In
the relational model of a database, all data is represented in terms of
tuples (rows), grouped into relations (tables). A database organized in
terms the relational model is a relational database.